1. Field of the Invention
The invention relates generally to agricultural equipment, such as harvesters, and more specifically, to spreader arrangements on such harvesters for spreading agricultural material to a field.
2. Description of the Related Art
An agricultural harvester known as a “combine” is historically termed such because it combines multiple harvesting functions with a single harvesting unit, such as picking, threshing, separating and cleaning. A combine includes a header which removes the crop from a field, and a feeder housing which transports the crop matter into a threshing rotor. The threshing rotor rotates within a perforated housing, which may be in the form of adjustable concaves and performs a threshing operation on the crop to remove the grain. Once the grain is threshed, it falls through perforations in the concaves onto a grain pan. From the grain pan, the grain is cleaned using a cleaning system, and is then transported to a grain tank onboard the combine. A cleaning fan blows air through the sieves to discharge straw, chaff and other debris toward the rear of the combine.
During the process of harvesting, crop material other than grain (MOG) is intended to be expelled from the combine. This material is usually derived from one of two areas, the threshing rotor or the cleaning system. The material expelled from the threshing rotor is generally referred to as straw and the material expelled from the cleaning system is generally referred to as chaff. This material or crop residue is typically dealt with by spreading or windrowing.
Spreading is accomplished using a mechanical device termed a spreader to distribute the straw and/or chaff substantially evenly from the rear of the combine. This spread material is usually chopped to as short a length as possible so that when it is spread it will break down as quickly as possible and not interfere with tillage or seeding operations.
Windrowing refers to the process of dropping straw directly behind the combine in a continuous stream. The purpose of doing this is usually to allow post harvest processing of the straw such as shaping it into bales. In this process, the straw is usually allowed to pass through the combine with as little interference as possible so that it remains as close as possible to its original length and condition.
U.S. Patent Application Publication No. 2015/0011276A1 (which is assigned to the assignee of the present invention) discloses a spreader arrangement which simply and effectively allows both spreading and windrowing from the rear of the harvester. A selectively movable swath door at the upper rear of the straw hood is movable between a first position directing crop material to the spreader discs, and a second position directing crop material to a windrow chute. The windrow chute folds up and out of the way to the rear of the straw hood when the spreader arrangement is in the spreading mode.
What is needed in the art is a spreader arrangement which can be easily reconfigured between the spreading and windrowing modes.